mmSTM_STMHEER_OFFSET
WREG32(base_reg + mmSTM_STMHEER_OFFSET, lower_32_bits(input->he_mask));
WREG32(base_reg + mmSTM_STMHEER_OFFSET, upper_32_bits(input->he_mask));
WREG32(base_reg + mmSTM_STMHEER_OFFSET, 0);